Master making and feeding device for a printer

Abstract

A master making and feeding device for a printer includes a first conveying section and a second conveying section. When the first conveying section is perforating a stencil or after it has perforated a stencil, conveyance drive means drives the second conveying section at a preselected timing in order to feed the leading edge of the stencil to a print drum. At this instant, the conveyance drive means drives the second conveying section such that it conveys the stencil at a higher speed than the first conveying section. The device is capable of reducing a period of time necessary for the leading edge of the perforated stencil to be fed to the print drum and therefore a first print time.

What is claimed is:  
     
       1. A master making and feeding device for a printer, comprising: 
       first conveying means including a rotatable platen roller for pressing a stencil between master making means and said platen roller to thereby thermally perforate said stencil, and conveying said perforated stencil to a downstream side in a direction of stencil conveyance;  
       second conveying means arranged between said first conveying means and a print drum, around which the perforated stencil is to be wrapped around, for conveying said perforated stencil conveyed by said first conveying means toward said print drum; and  
       conveyance drive means for driving, at a preselected timing during or after a perforation of the stencil effected by said first conveying means, said second conveying means to thereby feed a leading edge of the perforated stencil to the print drum, and driving second conveying means such that said second conveying means conveys said perforated stencil at a higher speed than said first conveying means,  
       wherein said first conveying means comprises a first drive source while said second conveying means comprises a second drive source implemented by a pulse-drive motor, and wherein a stencil conveying speed of said first conveying means and a stencil conveying speed of said second conveying means both are variable, and  
       wherein said master making means is movable into and out of contact with said platen roller, wherein said first conveying means further comprises moving means for moving said master making means into and out of contact with said platen roller, and wherein said second conveying means is driven for the preselected period of time during or after a contact of said master making means with said platen roller, but just before a perforation of the stencil.  
     
     
       2. A device as claimed in  claim 1 , wherein after said second conveying means has been driven for the preselected period of time, said pulse-driven motor is excited up to a next drive of said second conveying means. 
     
     
       3. A device as claimed in  claim 2 , wherein in a stand-by state before perforation, in which said master making means is released from said platen roller by said moving means, an excitation of said pulse-driven motor is interrupted or a current to be fed to said pulse-driven motor is reduced up to the next drive of said second conveying means. 
     
     
       4. A device as claimed in  claim 3 , further comprising mode selecting means for allowing an operator of the printer to determine whether or not to select an operation for interrupting the excitation or reducing the current. 
     
     
       5. A device as claimed in  claim 4 , wherein said mode selecting means is positioned on an operation panel. 
     
     
       6. A device as claimed in  claim 1 , wherein when the perforated stencil is wrapped around the print drum, an excitation ON/OFF timing of said pulse-driven motor is variable. 
     
     
       7. A device as claimed in  claim 1 , wherein said pulse-driven motor comprises a stepping motor. 
     
     
       8. A master making and feeding device for a printer, comprising: 
       a first conveying section including a rotatable platen roller for pressing a stencil between a master making device and said platen roller to thereby thermally perforate said stencil, and conveying said perforated stencil to a downstream side in a direction of stencil conveyance;  
       a second conveying section arranged between said first conveying section and a print drum, around which the perforated stencil is to be wrapped around, for conveying said perforated stencil conveyed by said first conveying section toward said print drum; and  
       a conveyance drive section for driving, at a preselected timing during or after perforation of the stencil effected by said first conveying section, said second conveying section to thereby feed a leading edge of the perforated stencil to the print drum, and driving said second conveying section such that said second conveying section conveys said perforated stencil at a higher speed than said first conveying section,  
       wherein said first conveying section comprises a first drive source while said second conveying section comprises a second drive source implemented by a pulse-drive motor, and wherein a stencil conveying speed of said first conveying section and a stencil conveying speed of said second conveying section both are variable, and  
       wherein said master making device is movable into and out of contact with said platen roller, wherein said first conveying section further comprises a moving device for moving said master making device into and out of contact with said platen roller, and wherein said second conveying section is driven for the preselected period of time during or after contact of said master making device with said platen roller, but just before perforation of the stencil.  
     
     
       9. A device as claimed in  claim 8 , wherein after said second conveying section has been driven for the preselected period of time, said pulse-driven motor is excited up to a next drive of said second conveying section. 
     
     
       10. A device as claimed in  claim 9 , wherein in a stand-by state before perforation, in which said master making device is released from said platen roller by said moving device, an excitation of said pulse-driven motor is interrupted or a current to be fed to said pulse-driven motor is reduced up to the next drive of said second conveying section. 
     
     
       11. A device as claimed in  claim 10 , further comprising a mode selecting device for allowing an operator to determine whether or not to select an operation for interrupting the excitation or reducing the current. 
     
     
       12. A device as claimed in  claim 11 , wherein said mode selecting device is positioned on an operation panel. 
     
     
       13. A device as claimed in  claim 8 , wherein when the perforated stencil is wrapped around the print drum, an excitation ON/OFF timing of said pulse-driven motor is variable. 
     
     
       14. A device as claimed in  claim 8 , wherein said pulse-driven motor comprises a stepping motor. 
     
     
       15. A master making and feeding device for a printer, comprising: 
       first conveying means including a rotatable platen roller for pressing a stencil between master making means and said platen roller to thereby thermally perforate said stencil, and conveying said perforated stencil to a downstream side in a direction of stencil conveyance;  
       second conveying means arranged between said first conveying means and a print drum, around which the perforated stencil is to be wrapped around, for conveying said perforated stencil conveyed by said first conveying means toward said print drum; and  
       conveyance drive means for driving, at a preselected timing during or after a perforation of the stencil effected by said first conveying means, said second conveying means to thereby feed a leading edge of the perforated stencil to the print drum, and driving second conveying means such that said second conveying means conveys said perforated stencil at a higher speed than said first conveying means,  
       wherein said master making means is movable into and out of contact with said platen roller, wherein said first conveying means further comprises moving means for moving said master making means into and out of contact with said platen roller, and wherein said second conveying means is driven for the preselected period of time during or after a contact of said master making means with said platen roller, but just before a perforation of the stencil.  
     
     
       16. A master making and feeding device for a printer, comprising: 
       a first conveying section including a rotatable platen roller for pressing a stencil between a master making device and said platen roller to thereby thermally perforate said stencil, and conveying said perforated stencil to a downstream side in a direction of stencil conveyance;  
       a second conveying section arranged between said first conveying section and a print drum, around which the perforated stencil is to be wrapped around, for conveying said perforated stencil conveyed by said first conveying section toward said print drum; and  
       a conveyance drive section for driving, at a preselected timing during or after perforation of the stencil effected by said first conveying section, said second conveying section to thereby feed a leading edge of the perforated stencil to the print drum, and driving said second conveying section such that said second conveying section conveys said perforated stencil at a higher speed than said first conveying section,  
       wherein said master making device is movable into and out of contact with said platen roller, wherein said first conveying section further comprises a moving device for moving said master making device into and out of contact with said platen roller, and wherein said second conveying section is driven for a preselected period of time during or after contact of said master making device with said platen roller, but just before perforation of the stencil.